小编Fio*_*oni的帖子

我的底部导航栏在我的默认启动片段SearchFragment中不可见.如果我将开始片段更改为另一个例如MoreFragment,它会出现在其他所有内容上,除了SearchFragment,这是我理想的开始片段.

这是我的代码:

Main.java

import android.support.annotation.NonNull;
import android.support.design.widget.BottomNavigationView;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.view.MenuItem;



public class Main extends FragmentActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    if (savedInstanceState == null) {
           getSupportFragmentManager().beginTransaction().replace(R.id.activity_main, new SearchFragment()).commit();
    }

    BottomNavigationView bottomNavigation = (BottomNavigationView) findViewById(R.id.bottom_navigation);

    bottomNavigation.setOnNavigationItemSelectedListener(new BottomNavigationView.OnNavigationItemSelectedListener() {

        public boolean onNavigationItemSelected(@NonNull MenuItem item) {
            switch(item.getItemId()){
                case R.id.seach_tab:
                   SearchFragment sf=new SearchFragment();
                    FragmentManager fragmentmanager1=getSupportFragmentManager();
                    fragmentmanager1.beginTransaction()
                            .replace(R.id.activity_main, sf)
                            .commit();
                    break;


                case R.id.bookings_tab:
                    BookingsFragment bf=new BookingsFragment();
                    FragmentManager fragmentmanager2=getSupportFragmentManager();
                    fragmentmanager2.beginTransaction()
                            .replace(R.id.activity_main, bf)
                            .commit();
                    break;

                case R.id.account_tab:
                    ProfileFragment …